NASA // Current TV

'Seven minutes of terror': Mars landing will be a nail-biter

Scientists are utilizing a complicated new 'sky crane' technique for landing... more

coolplanet
added this
10 months ago
|
17 comments

NASA selects space taxi developers for U.S. International Space Station comeback

NASA announced Friday its intentions of a United States return to the International... more

stormchaser4850
added this
10 months ago
|
0 comments

NASA's newest Mars rover set for complicated landing Sunday night

NASA's newest Mars rover, Curiosity, is set to make a complicated landing on the... more

stormchaser4850
added this
10 months ago
|
3 comments

New Photos Reveal Fate of American Flags Left on the Moon (VIDEO)

"Most scientists had assumed the flags hadn’t survived more than four... more

StewSteve
added this
10 months ago
|
1 comment

Unprecedented Greenland Ice Sheet Surface Melt

July 24, 2012: For several days this month, Greenland's surface ice cover melted over a larger area than at any time in more than 30 years of satellite observations. Nearly the entire ice cover of Greenland, from its thin, low-lying coastal edges to its two-mile-thick center, experienced some degree of melting at its surface, according to measurements from three independent satellites analyzed by NASA and university scientists.

On average in the summer, about half of the surface of Greenland's ice sheet naturally melts. At high elevations, most of that melt water quickly refreezes in place. Near the coast, some of the melt water is retained by the ice sheet and the rest is lost to the ocean. But this year the extent of ice melting at or near the surface jumped dramatically. According to satellite data, an estimated 97 percent of the ice sheet surface thawed at some point in mid-July.

Researchers have not yet determined whether this extensive melt event will affect the overall volume of ice loss this summer and contribute to sea level rise.

"The Greenland ice sheet is a vast area with a varied history of change. This event, combined with other natural but uncommon phenomena, such as the large calving event last week on Petermann Glacier, are part of a complex story," said Tom Wagner, NASA's cryosphere program manager in Washington. "Satellite observations are helping us understand how events like these may relate to one another as well as to the broader climate system."

Son Nghiem of NASA's Jet Propulsion Laboratory in Pasadena, Calif., was analyzing radar data from the Indian Space Research Organisation's (ISRO) Oceansat-2 satellite last week when he noticed that most of Greenland appeared to have undergone surface melting on July 12. Nghiem said, "This was so extraordinary that at first I questioned the result: was this real or was it due to a data error?"

Nghiem consulted with Dorothy Hall at NASA's Goddard Space Flight Center in Greenbelt, Md. Hall studies the surface temperature of Greenland using the Moderate-resolution Imaging Spectroradiometer (MODIS) on NASA's Terra and Aqua satellites. She confirmed that MODIS showed unusually high temperatures and that melt was extensive over the ice sheet surface.

Thomas Mote, a climatologist at the University of Georgia, Athens, Ga; and Marco Tedesco of City University of New York also confirmed the melt seen by Oceansat-2 and MODIS with passive-microwave satellite data from the Special Sensor Microwave Imager/Sounder on a U.S. Air Force meteorological satellite.

The melting spread quickly. Melt maps derived from the three satellites showed that on July 8, about 40 percent of the ice sheet's surface had melted. By July 12, 97 percent had melted.

This extreme melt event coincided with an unusually strong ridge of warm air, or a heat dome, over Greenland. The ridge was one of a series that has dominated Greenland's weather since the end of May. "Each successive ridge has been stronger than the previous one," said Mote. This latest heat dome started to move over Greenland on July 8, and then parked itself over the ice sheet about three days later. By July 16, it had begun to dissipate.

Even the area around Summit Station in central Greenland, which at 2 miles above sea level is near the highest point of the ice sheet, showed signs of melting. Such pronounced melting at Summit and across the ice sheet has not occurred since 1889, according to ice cores analyzed by Kaitlin Keegan at Dartmouth College in Hanover, N.H. A National Oceanic and Atmospheric Administration weather station at Summit confirmed air temperatures hovered above or within a degree of freezing for several hours July 11-12.

"Ice cores from Summit show that melting events of this type occur about once every 150 years on average. With the last one happening in 1889, this event is right on time," says Lora Koenig, a Goddard glaciologist and a member of the research team analyzing the satellite data. "But if we continue to observe melting events like this in upcoming years, it will be worrisome."July 24, 2012: For several days this month, Greenland's surface ice cover melted... more

coolplanet
added this
10 months ago
|
57 comments

Ride, Sally! Ride! First American Woman in Space Passes Away

First off, let me just say, I don’t mourn astronauts. I celebrate them. If I had... more

StewSteve
added this
10 months ago
|
0 comments

First American woman to fly to space, Sally Ride dead at age 61

Sally Ride, the first American woman to fly to space, has died, according to Sally... more

stormchaser4850
added this
10 months ago
|
9 comments

What Space Smells Like and How to Recreate It

Space smells. But what does it smell like? Different astronauts and scientists have... more

Vierotchka
added this
10 months ago
|
2 comments

43rd Moon Landing Anniversary: Pictures Of Historic Landing

The Saturn V rocket carrying the Apollo 11 crew had blasted off from Florida about 109... more

JanforGore
added this
10 months ago
|
25 comments

Giant storm on Saturn illuminates daytime blue lightning, NASA orbiter captures

NASA says they captured a rare seen during a storm on Saturn last year, the largest... more

stormchaser4850
added this
10 months ago
|
0 comments

RAW Nasa Footage Of Dramatic Solar Flare (solar-storm 14.07.2012)

FreePressTV
added this
10 months ago
|
0 comments

Hidden Portals in Earth's Magnetic Field

A NASA-sponsored researcher at the University of Iowa has developed a way for... more

rodstradamus
added this
10 months ago
|
11 comments

Study Finds Ancient Warming Greened Antarctica

Pollen grains and leaf waxes record vegetation on Antarctica during a time of global... more

joeeddy
added this
11 months ago
|
0 comments

Far out man! – Black Hole Growth Found to be Out of Synch

Two black holes are challenging the prevailing idea of how giant black holes grow in... more

joeeddy
added this
11 months ago
|
0 comments

NASA Discovers Unprecedented Blooms of Ocean Plant Life

Scientists have made a biological discovery in Arctic Ocean waters as dramatic and... more

joeeddy
added this
12 months ago
|
0 comments

So will a partial eclipse of a nearly-full moon = more, or less craziness in the news?

"On June 4th, 2012, there's going to be a full Moon. According to Native... more

attilatheblond
added this
12 months ago
|
14 comments

New York Roofs Go Cool ~ Enhance Your Albedo

On the hottest day of the New York City summer in 2011, a white roof covering was... more

coolplanet
added this
12 months ago
|
6 comments

SpaceX's Dragon spacecraft docks with the International Space Station - Hangouts On Air

Is there anything private companies will not be able to do? From SpaceX to companies... more

jdooes
added this
12 months ago
|
0 comments

SpaceX Launch: Commercial Spaceflight is Here

Late tomorrow evening (AEST), all going well, a Falcon 9 rocket will lift-off from... more

coolplanet
added this
1 year ago
|
24 comments

Game Over for the Climate - Jim Hansen on Tar Sands

By James Hansen, NASA New York Times | May 9, 2012 GLOBAL warming isn’t a... more

coolplanet
added this
1 year ago
|
25 comments

select your country

Community Spotlight

TAGS

tagged w/ NASA

top videos

find current on tv

find current online

recent comments

© 2013 Current TV, LLC All Rights Reserved

the basics

follow us online

tools

stay in touch

© 2013 Current TV, LLC
All Rights Reserved